Long-term objectives of this project are to identify risk factors for the development of hypertensive (HTN) end stage renal disease (ESRD), especially in blacks, and to develop techniques to remove/diminish the effects of factors which compromise renal function (RF), reducing the incidence of ESRD. The specific aims of this proposed pilot center are to: 1) demonstrate the ability to identify and recruit minority patients (pts) with RF compromised by HTN, 2) demonstrate the ability to acquire the data needed to test a HTN-ESRD hypothesis, in a full-scale clinical trial, 3) assess factors which influence, and develop techniques which ensure, compliance with clinic visits and medication for the target popu- lation, 4) provide data on the best methods to estimate/determine how well the targeted blood pressure (TBP) goal is being achieved, 5) determine the relative efficacy of diuretics (D), calcium channel blockers (CCB), and angiotensin converting enzyme inhibitors (ACE-I) in obtaining the TBP and the relative frequency of side effects, and 6) develop and test a system/method for tracking adverse effects from study medications and procedures in relationship to the TBP and the progression of RF, in an unbiased fashion. At least 50 pts. (50% male and 70% or more black) who have mild-moderate HTN with compromised RF secondary to HTN, will be identified and recruited. After screening to determine their eligibility according to established inclusion/exclusion criteria, they will be briefed on their HTN-RF status, the probable natural history of the condition, and the goals, aims, and procedures of the study. Pts. will be screened to determine willingness to participate and comply with the protocol requirements, and an informed Consent obtained; after a 2 week (wk) washout period (if needed), a 2 wk period for acquiring baseline data will be started. Data will include documentation of BP levels (office and 24hr. ambulatory), glomerular filtration rate (GFR), and renal biopsy (RB). Pts. will then be randomized to 1 of 3 classes of antihypertensive medications--loop D, CCB, or ACE-I. Medication doses will be titrated in 3 steps, to a predetermined dose if needed, to reach the TBP equal to or less than 140/90 or 125/80mmHg. If needed, 2 or all 3 classes will be given, increasing the dose of each in a step-wise fashion, until TBP is achieved. Pts. will be contacted at 2 wk intervals; by phone every 4 wks, and by visits every 4 wks, with a staggered 2 wk contact period. The frequent contacts are to monitor compliance, BP, and GFR, which will be determined at baseline, and at 12 mos. RB will be obtained at baseline and 12 mos. At least 25 pts. will finish the 12 mos protocol and provide data for analysis.